<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>下拉菜单</title>
  <style>
    .dropbtn {
      background-color: #4CAF50;
      color: white;
      padding: 16px;
      font-size: 16px;
      border: none;
      cursor: pointer;
    }

    .dropdown {
      position: relative;
      display: inline-block;
    }

    .dropdown-content {
      display: none;
      position: absolute;
      background-color: #f9f9f9;
      min-width: 160px;
      box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
      z-index: 1;
    }

    .dropdown-content a {
      color: black;
      padding: 12px 16px;
      text-decoration: none;
      display: block;
    }

    .dropdown-content a:hover {background-color: #ffff00}

    .dropdown:hover .dropdown-content {
      display: block;
    }

    .dropdown:hover .dropbtn {
      background-color: #333;
    }
  </style>
</head>
<body>
<div class="dropdown">
  <button class="dropbtn">Dropdown</button>
  <div class="dropdown-content">
    <a href="#">Link 1</a>
    <a href="#">Link 2</a>
    <a href="#">Link 3</a>
  </div>
</div>
</body>
</html>